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I am a residential designer here in Bellingham and have designed cob homes and have gotten permits for them.

There is no effect on zoning for a cob home. A cob is a type of construction. If they are building a single family home in single family zoning it doesn't matter what they make it out of for zoning. For permitting that's a different story. The easiest way to permit a cob home is to do cob in-fill where the cob is not weight bearing - meaning post and beam provides the main structural support and the cob fills in btwn the structural supports.

The other item is energy code - a solid cob wall will not meet R-21 min. wall insulation for energy code requirements. There are other structural issues that need to be met for permit that are too lengthy to go into but I would highly recommend the owners or you go talk to the building dept. for either City or County - where ever they are planning to build. International Building Code allows for "alternative building" but you must prove it meets current building code and structural requirement - like any other home is required to do.

Unless they have done cob before, it is always a good idea to do a small outbuilding like a garden shed in cob before they do a whole house. Cob needs heat to dry out so timing is essential in our cool climate, and cob is labor intensive - lots of friends are needed as well as access to good clay soil - sometime not found on property with nice sandy loam!

There are a couple cob residences here in Bham. You might get messages from others in the Transition Whatcom list serv. from those folks.

You as a realtor might check to see how banks feel about loans for cob home construction. And home insurance companies might have additional criteria for non-standard construction.

An engineer will most likely need to be involved - not a big deal - but something to add to the list.

One area of particular concern in the roof to top of wall connection as well as foundation. Some cob books show construction techniques that absolutely will not pass code or permit requirements - not an issue if you are not needing a building permit for an out-building, or building in a jurisdiction that does not require a building permit - some out the way places don't. All the citiies here in WA do, however. That said, there are cob homes that have built without permits - it's not legal, and you usually can't sell them without bringing them up to Code. Sometimes that can be done, sometimes it can't. I was involved in the sale of one property built with conventional wood stud construction but with no permits for anything and owner tried to sell the property. The County stepped in and required new owners to verify all the construction, plumbing and electrical was done to current code and pay for full permits - that were not paid for when built. It was easier to bull doze the house and start over then to do try to do everything after the fact. Not to mention expensive and pay the penalties.

I was also involved in getting engineering for a cob home that had a permit and was finished, but no approved engineering and no final occupancy permit from the city. We found an engineer who specialized in alternative construction, he figured out ways for the home to meet engineering requirements by adding a lot of steel bracing, and the building dept. approved it and gave the owners the final occupancy permit - one of the first cob residences in WA state to get a permit - it was cob infill with post and beam as structural support.

I am a residential designer here in Bellingham and have designed cob homes and have gotten permits for them.

There is no effect on zoning for a cob home. A cob is a type of construction. If they are building a single family home in single family zoning it doesn't matter what they make it out of for zoning. For permitting that's a different story. The easiest way to permit a cob home is to do cob in-fill where the cob is not weight bearing - meaning post and beam provides the main structural support and the cob fills in btwn the structural supports.

The other item is energy code - a solid cob wall will not meet R-21 min. wall insulation for energy code requirements. There are other structural issues that need to be met for permit that are too lengthy to go into but I would highly recommend the owners or you go talk to the building dept. for either City or County - where ever they are planning to build. International Building Code allows for "alternative building" but you must prove it meets current building code and structural requirement - like any other home is required to do.

Unless they have done cob before, it is always a good idea to do a small outbuilding like a garden shed in cob before they do a whole house. Cob needs heat to dry out so timing is essential in our cool climate, and cob is labor intensive - lots of friends are needed as well as access to good clay soil - sometime not found on property with nice sandy loam!

There are a couple cob residences here in Bham. You might get messages from others in the Transition Whatcom list serv. from those folks.

You as a realtor might check to see how banks feel about loans for cob home construction. And home insurance companies might have additional criteria for non-standard construction.

An engineer will most likely need to be involved - not a big deal - but something to add to the list.

One area of particular concern in the roof to top of wall connection as well as foundation. Some cob books show construction techniques that absolutely will not pass code or permit requirements - not an issue if you are not needing a building permit for an out-building, or building in a jurisdiction that does not require a building permit - some out the way places don't. All the citiies here in WA do, however. That said, there are cob homes that have built without permits - it's not legal, and you usually can't sell them without bringing them up to Code. Sometimes that can be done, sometimes it can't. I was involved in the sale of one property built with conventional wood stud construction but with no permits for anything and owner tried to sell the property. The County stepped in and required new owners to verify all the construction, plumbing and electrical was done to current code and pay for full permits - that were not paid for when built. It was easier to bull doze the house and start over then to do try to do everything after the fact. Not to mention expensive and pay the penalties.

I was also involved in getting engineering for a cob home that had a permit and was finished, but no approved engineering and no final occupancy permit from the city. We found an engineer who specialized in alternative construction, he figured out ways for the home to meet engineering requirements by adding a lot of steel bracing, and the building dept. approved it and gave the owners the final occupancy permit - one of the first cob residences in WA state to get a permit - it was cob infill with post and beam as structural support.